© Andy Roberts 1997. Pictured comet is C/1995 O1 Hale-Bopp.

C/2017 O1 (ASASSN) reaches its brightest

Dominic Ford, Editor
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Comet C/2017 O1 (ASASSN) is forecast to reach its brightest, at around mag 8.9. It will lie at a distance of 1.49 AU from the Sun, and at a distance of 0.71 AU from the Earth.

From Ashburn, it will be visible in the morning sky, becoming accessible at around 21:07, when it rises 21° above your north-eastern horizon. It will then reach its highest point in the sky at 04:12, 76° above your northern horizon. It will be lost to dawn twilight at around 06:13, 65° above your north-western horizon.

Begin typing the name of a town near to you, and then select the town from the list of options which appear below.

For more information about its path across the sky, see In-The-Sky.org's ephemeris page for comet C/2017 O1 (ASASSN).

This event was automatically generated on the basis of orbital elements published by the Minor Planet Center (MPC), and is updated daily (last update, 22 Oct 2018).

Note that the future positions of comets are typically known with a high degree of confidence, but their brightnesses are often much more unpredictable, since it is impossible to predict with certainty how they will respond as they move closer to the Sun. Magnitude estimates should be assumed to be highly provisional more than a few weeks in advance.

Printable finder charts

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The exact position of comet C/2017 O1 (ASASSN) will be:

Object Right Ascension Declination Constellation Magnitude
Comet C/2017 O1 (ASASSN) 04h42m50s +52°31' Perseus 8.9

The coordinates are given in J2000.0.

The sky on 16 October 2017
Twilight ends
Twilight begins

26-day old moon
Waning Crescent


26 days old

Rise Culm. Set
Mercury 07:47 13:15 18:43
Venus 05:35 11:40 17:44
Moon 04:06 10:36 17:05
Mars 05:03 11:15 17:27
Jupiter 07:58 13:25 18:52
Saturn 12:11 16:57 21:43
All times shown in EDT.


The circumstances of this event were computed using the DE405 planetary ephemeris published by the Jet Propulsion Laboratory (JPL).

This event was automatically generated by searching the ephemeris for planetary alignments which are of interest to amateur astronomers, and the text above was generated based on an estimate of your location.

Image credit

© Andy Roberts 1997. Pictured comet is C/1995 O1 Hale-Bopp.




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